In a large mixing bowl, cream 1 cup sugar and margarine until light and fluffy. Beat in sour cream and eggs. Add flour, baking powder and baking soda and beat on low speed until incorporated. Stir in apples.

Pour batter into prepared pan and sprinkle with combination of remaining ¼ cup sugar and cinnamon.

Bake until tester comes out with just barely moist crumbs, about 60 minutes. Serve warm or at room temperature.